Merge "Remove ndk_platform backend. Use the ndk backend." am: 85705f6c86 am: e66b2b4015 am: ff366fab5f am: 474207368d

Original change: https://android-review.googlesource.com/c/platform/system/vold/+/1778413

Change-Id: If2515a91c335a804ac0f64737b9b8c9567e1f04d